Furnace front



L H. HUME.

FURNACE FRONT.

APPLICATION man nic. 4. isla.

1,425,095. Patentedfmg. s, 1922.

3 SHEETS-SHEET l.

l. H. HUME.

FURNACE FRONT.

APPucATloN FILED Dsc. 4. 1919.

1 ,425,095 Patented Aug. 8, 1922.

3 SHEETS-SHEET 2.

Fla

l. H. HUME.

FURNACE FRNT.

APPLIcATloN mso Dsc. 4. 1919.

1 ,425 ,095. Patented Aug. 8, 1922.

3 SHEETS-SHEET 3.

17H/Ew rv M144. M41/ M UNITED STATES PATENT OFFICE.

JAMES HOWDEN HUME, oF GLASGOW, SCOTLAND, .asslefr'roa` To JAMES HowDEN @L COMPANY, LIMi'rEn, oF GLASGOW', SCOTLAND.

FURNACE FRONT.

Specification of Letters Patent.

Patented Aug. 8', 1922.

Application led December 4, 1919.v Serial No. 342,337.

To all "t0/0m it may com-.erft

Be it known that I. JAMES HowDEN HUME, a subject of the King of the United Kingdom of Great Britain and Ireland. and residing at Glasgow, Scotland, have invented a certain new and useful Improvement in Furnace Fronts, of which the following is a specification.

This invention relates to improvements in furnace fronts for forced draught installations more particularlyy to fronts fitted with side air valves as in installations of the Howden type.

The invention has been primarily designed for furnaces adapted to operate with elther solid or liquid fuel` it being understood, however, that the invention is also applicable to furnaces for use with solid fuel only.

It has already been proposed to provide in such furnaces interconnected side air valves operatively connected to a device for locking the firing door contrived to insure that the door cannot be opened unless and until the Side air valves are closed.

Certain constructions of furnace front do not lend themselves to the interconnection of the side air valves. There is also to be taken into consideration that furnace users to whom the employment of separately operated side air valves is familiar do not readily become accustomed to a construction having a single means for operating the side air valves.

The present invention provides a construction having separately operable side air valves, each valve being operatively connected with means for locking the door so that the door cannot be opened unless and until both side air valves are closed.

In the accompanying drawings Fig. 1 is a frontelevation, Fig. 2 a vertical section and rig. 3 a fragmentary horizontal section of a furnace front embodying the invention. Fig. 4 is a view corresponding to Fig. 1 showing a modification.

Fig. 5 is a vertical section of the furnace front. Fig. 6 is a horizontal detail section showing the connection of the left handle with the left air valve: Fig. 6 is a horizontal detail section showing the connection of the right handle with the right air valve, and Fig. 7 is a fragmentary enlarged view of the door locking device shown in Fig. l.

Similar reference numerals denote similar parts in the several views.

Referring to Figs` 1 to 3, 1 denotes the firing door at the opposite sides of which are the handles 2 and 3 for operating the side air valves. Operatively connected with the left hand handle 2 is a locking bolt 4 slldable in a guide member 5. In the position illustrated in Fig. 1 the bolt 4 is clear of the door, the handle 2 being in the position corresponding to the closed position of the left hand side air valve. When the handle 2 1s moved in clockwise direction to open the alr valve, the bolt 4 is protruded and occupiesa position in interfering relation with the firing door so that the door 1 cannot be opened so long as the left hand side air valve is open. Connected to the handle 3 for the right .hand side air valve is a rod 6 slidable in guldes 7 and having an upward projection 8. In the position shown in Fig. 1 the projection 8 is clear of the door l.y theA handle 3 belng in the position corresponding to the closed position of the right hand side air valve. When the handle 3 is moved in counter-clockwise direction to open the right hand side air valve, the projection 8 is shifted to the right so that it comes into interfering relation with the firing door 1; that is, the door 1 cannot be opened so long as the ri ht hand side air valve is open.

he handle 2 is connected with a shaft 9 on which is mounted a bevel gear wheel 10 meshing with a similar bevel gear 11 fixed to a shaft 12 which carries the left hand side air valve 13, so that when the handle 2 is moved clockwise to the position denoted by broken lines in Fig. 7, the bolt 4 will be 1n position to lock the door 1 and the said valve will be opened; and whtn the said handle is in the position shown in Fig. 1 and in full lines in Fig. 7, the said valve will be closed and the door 1 unlocked.

In a similar manner and by similar means the handle 3 is connected with the right hand side air valve 13", as will be understood from Fig. 6a.

The construction shown in Fig. 4 is sub` stantially similar t0 that of Fig. 1, the rod 6 being. however. differently connected to the handle 3 and being slidable in guide members 7', 7' between which the slide rod 6 has an upward projection 8 shiftable into and out of interfering relation with a depending projection 1* on the firing door.

I claim In combination with a furnace front for forced draught installations, a lring door, In testimony Twhereof I hhve signed my two alr valves, ons at each 51de of sind firing name to thls speclcatlon 1n the presence of door two operating handles` one for each two subscribing Witnesses. 10 valve, and two door locking members, one A JAMES HODEN HUME.

5 connected to each handle for preventing the Witnesses:

opening of said rlng door until both han- KATE FOTHERINGHAM,

dles are in position to'close both valves. ISABEL ROLLO. 

